Boronic acid-functionalized molybdenum disulfide quantum dots for the ultrasensitive analysis of dopamine based on synergistic quenching effects from IFE and aggregation

Abstract

Herein, a novel fluorescent material, boronic acid-functionalized molybdenum disulfide quantum dots (B-MoS₂ QDs) produced by an amidation reaction between 3-aminobenzeneboronic acid and previously prepared molybdenum disulfide quantum dots (MoS₂ QDs), was prepared to fabricate a rapid and sensitive platform for the quantitative analysis of dopamine. This material exhibits strong fluorescence, excellent salt tolerance and light fastness. In particular, the quantum yield of this material is about 21.1 times that of its fundamental material, MoS₂ QDs. Notably, owing to an interesting synergistic effect between the inner filter effect and the aggregation quenching effect, this material was successfully applied for the determination of dopamine in the linear range 0.25-35 μmol L^-1 with the detection limit of 0.087 μmol L^-1; moreover, B-MoS₂ QDs manifested better selectivity in the presence of multiple interferences due to their inert surface. As expected, this proposed material shows satisfactory performance in human serum; thus, the present study exploits a new avenue for the application of functionalized MoS₂ QDs in fluorescence sensing.